Dec 08, 2002Dec. 9, 2002 -- There are three major elements that make up the cost of an RFID tag: the silicon microchip, the copper antenna and the process of attaching the antenna to the chip. Flint Ink has come up with a way to print inexpensive antennas using conductive inks. The technology could have a major impact on the printing and packaging industry.
Flint, of course, isn't the only company that has developed conductive inks. The technology has been around for years. But Flint was one of the first makers of conductive inks to understand their value to RFID. The company was among the earliest sponsors of the Auto-ID Center.
Flint has been working with a company in Scotland called RT Circuits, which has developed proprietary technology for printing conductive antennas using graphics arts lithography. Flint shared its knowledge of conductive inks, and together, the companies developed a system that works.
Flint has also been working with Alien Technology, which has created a microchip based on the Auto-ID Center's electronic product code (EPC) specification. By connecting a tiny plastic strap with Alien's chip inside to a piece of paper with the conductive ink printed on it, the two have made fully functioning RFID tags.
At the last Auto-ID Center board meeting, Flint and Alien showed that a tag with a printed antenna could be read from three to four meters (10 to 13 feet). The Auto-ID Center's specification calls for a read range of only one meter.
"The vision is to move from the etched, solid metal antennas to the printed antennas," says Dan Lawrence, Flint Ink's manager of print as manufacture. "Then, you have the opportunity to get into the large-scale production packaging environment and move from a separate RFID tag concept to an integrated RFID tag, which would be done by our customer, who would be the converter."
The ink Flint developed has silver in it. One reason Flint chose the precious metal is because it doesn't oxidize and degrade the way copper does. The ink is expensive compared to most ordinary commercial inks, but by printing very thin layers of ink and keeping the antenna size small, the cost of the printed antenna can be kept low.
"An antenna that costs a penny or two is certainly possible," says Lawrence. "We are looking to drive that down even further still through clever antenna design and materials formulation."
Flint is working on a variety of inks that can be used in each of the major types of printing processes. Since radio waves travel through most packaging materials, packagers will have a lot of flexibility in how they print the antenna. They could print it inside of the box. They could laminate it inside the package or print it on the outside and print over it.
Several of the Auto-ID Center sponsor companies are already doing evaluation trials of the printed antenna. "They hope to move it into the main stream within a year or two, maybe sooner," say Lawrence. "Widespread adoption -- that's harder to predict. But as the benefits are demonstrated and there is an open standard, companies will become more comfortable adopting this technology, and the benefits will drive it further still."
